'Add to iTunes as a Spoken Track.workflow' is found in /System/Library/Services. Navigate to that location and double-click the workflow file. Don't Panic! We are not going to modify this file; we're just looking for error messages when it's opened in Automator.
Automator complains that the actions 'Import Audio Files' and 'Add Songs to Playlist' could not be loaded because the application iTunes is the wrong version.
Navigate to /System/Library/Automator. WARNING: Do not modify files found under /System! Copy 'Import Audio File.action' and 'Add Songs to Playlist.action' to a convenient location in your User area. After copying, right-click on one of those files and select 'Show Package Contents.' Inside the package you will find a Contents folder within which is an Info.plist file. Open this file in your favorite text editor. Look for a section of text that looks something like this:
<array> <dict> <key>Display Name</key> <string>iTunes</string> <key>Resource</key> <string>com.apple.iTunes</string> <key>Type</key> <string>application</string> <key>Version</key> <string>4.6</string> </dict> </array>
Launch Automator. Select File » Import Actions... and choose the actions you just modified. These modified actions will be placed in ~/Library/Automator. You may want to color-label them so that they can be removed if/when Apple fixes this problem. You probably will want to log out/log back in to get your workflow working.
This process should work for any iTunes-related Automator action that broke when iTunes 10.0 was released.
[crarko adds: I tested this, and it works exactly as described. Presumably Apple will fix this shortly.]

